various apps keep not responding locking up phone

Apps go from working to not responding continuously. Not always same apps, just random. Locks up phone or makes so slow I can t use it.

Also constantly resetting Display time back to 15 seconds on its own and putting itself into airplane mode. Even while in middle of phone call, whichs cuts call off. Any help appreciated. I've tried to fix all these problems over past month but can't find answers. THANK YOY!!